Best use of 6 ESX CPU License

[TonyJK]

We are currently running three ESX 3.5 Hosts at HQ. We are going to deploy ESX Hosts at one of our remote site. Currenly, we have 6 extra ESX CPU license available that can be used by servers at the remote site.

We would like to set up 2 ESX Host Servers at Remote site with DRS and HA enabled. We would like to know should be set up

1) 1 x 4 CPU Host + 1 x 2 CPU Host

2) 2 x 3 CPU Host ?

Moreover, does it mean that we should create another Cluster for those ESX Hosts at remote site ? In this way, there will be 2 clusters at our site - 1 for HQ, 1 for Remote Site ?

We have been using EMC CX3-20 at our HQ. If we consider using the remote site as a DR site (If possible), is it necessary for us to add more HD to our existing CX3-20 SAN at HQ ?

Thanks

[MR-T]

If you require HA & DRS at the remote site, you will need to create a second cluster (Unless the remote site shares the same storage via a stretched fabric).

I don't know what to say regarding the licences, go with the best boxes you can within the budget you have available. Keeping them identical will make life easier.

[spex]

To avoid unnecessary cost I would only use as many licence's as you really need. I don't know your performance needs at remote, but consider following scenarios:

If your remote site is a small location:

2 or 3 server (2 cpu sockets) - each only with 1 CPU - 4 core - 16GByte RAM

(VMware allows to split 2 cpu licenses). Later if needed install second cpu.

If your remote site is a large location:

2 or 3 server (4 cpu sockets) - each with 2 CPU - 4core 64 Byte RAM

Later if needed install 2 more cpu's

Regards Spex

[AntonVZhbankov]

It depends on your needs. CPU license is socket based, so 6 licenses mean you can have 6*4 = 24 cores. In most cases 8 cores per host is more than enough.

Do you really need 16-core host? 3 hosts are always better than 2 because of availability. Let's imagine you lost one host - in case of 3 same hosts you lost only 33% processing power and you can restart VM's on 2 remaining hosts. With HA you can do it for sure and do it automatically. In the case of 2 hosts, 4 way and 2 way, if 2 way host is down - 4 way can take load the same way as with 3 2-way hosts, you just have to have enough memory on it. But if 4-way host fails only 33% processing power remains.

[kjb007]

Personally, I don't like having an uneven number of sockets used, other than 1. So, I would not populate a server with 3 CPU. Either keep it at 2 or 4, but not 3. If you have the hardware, I'd use 3x2-CPU servers, or, go with option 1, 1x4-CPU and and 1x2-cpu.

-KjB

[AntonVZhbankov]

kjb007, is this just a matter of taste or you have technical considerations?

With such a small number of hosts is better to have same CPU power on both hosts. If host fails - 50% power remains. With 4 and 2 way servers - 33% and 66%. As for me, 2 quad CPUs are enough for almost any ESX host unless you are absolutely sure you need 4 quads. Set up third host to gain redundancy and load balancing.

Or you can set up 6 single CPU hosts with 4-cores per CPU. For ex. buy 6 dual socket servers with 1 CPU installed only. This is the most redundant way. And if you need more CPU power - you can always buy some more licenses.

[kjb007]

I've seen this as a requirement on some hardware, and prefer it this way as well. One certain other hardware, I don't remember exactly which, but the sockets, unless it was only 1 CPU, had to be balanced, so you had to use 2, 4, 8. Depends on the chipset they are using, I suppose.

If you are concerned with DR, I can tell you that in my environment, memory appears to be the limiting factor, and not CPU.

-KjB

[depping]

it's not an option in your post but I would go for 3 x 2 cpu server.

Duncan

My virtualisation blog:

[depping]

i would go for 3 x 2cpu server.

Duncan

My virtualisation blog: